#!/usr/bin/env python3
import random
num_list = []
def random_num():
    for x in range(0,10):
        num_list.append(str(x))

    for y in ('a','b','c','d','e','f'):
        num_list.append(y)
    return num_list

mac_list = []
mac = ""
def random_mac():
    for x in range(6):
        num_list = random_num()
        random_list = random.sample(num_list,2)#随即从列表num_list中选择2个长度的值
        random_str = random_list[0]+random_list[1]
        mac_list.append(random_str)
    for y in range(6):
        if y==0:
            mac = mac_list[y]
        else:
            mac = mac +":"+ mac_list[y]
    return mac


if __name__ == "__main__":
    print(random_mac())
